#include "stm32f10x.h"                  // Device header

int16_t Encoder_Count;

void Encoder_Init(void)
{
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
	
	GPIO_InitTypeDef GPIO_InitStructure;
 	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;
 	GPIO_Init(GPIOB, &GPIO_InitStructure);
//	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
// 	GPIO_Init(GPIOB, &GPIO_InitStructure);
	
	//AFIO中断引脚选择,Don`t FORGET IT!
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource0);
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource1);

	EXTI_InitTypeDef EXIT_Initstruture;
	EXIT_Initstruture.EXTI_Line = EXTI_Line0 | EXTI_Line1;  //TWO GE
	EXIT_Initstruture.EXTI_LineCmd = ENABLE;
	EXIT_Initstruture.EXTI_Mode = EXTI_Mode_Interrupt;
	EXIT_Initstruture.EXTI_Trigger = EXTI_Trigger_Falling;
	EXTI_Init(&EXIT_Initstruture);
	
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
	
	// FIRST
	NVIC_InitTypeDef NVIC_InitStructure;
	NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
	NVIC_Init(&NVIC_InitStructure);
	//SECOND
	NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
	NVIC_Init(&NVIC_InitStructure);
}


int16_t Encoder_Count_Get(void)
{
	int16_t Temp;
	Temp = Encoder_Count;
	Encoder_Count =0;
	return Temp;
}

//FIRST
void EXTI0_IRQHandler(void)
{
	if (EXTI_GetITStatus(EXTI_Line0)==SET)
	{
		if (GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_1)==0)
		{
			Encoder_Count++;
		}
	}
	EXTI_ClearITPendingBit(EXTI_Line0);
}

//SECOND
void EXTI1_IRQHandler(void)
{
	if (EXTI_GetITStatus(EXTI_Line1)==SET)
	{
		if (GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_0)==0)
		{
			Encoder_Count--;
		}
	}
	EXTI_ClearITPendingBit(EXTI_Line1);
}
